diff --git a/async/README.md b/async/README.md
index 01e27c3..76e1405 100644
--- a/async/README.md
+++ b/async/README.md
@@ -331,9 +331,9 @@ Executed instructions per fixed workload (`async/bench/icount/`), measured under
 | `kernel_float` | 2,427,595,993 | 109,298,076 | 422,160,541 |
 | `kernel_q15` | 1,123,119,218 | 192,431,957 | 187,429,187 |
 | `kernel_q31` | 1,169,957,251 | 221,164,795 | 194,964,122 |
-| `pipeline12_q15` | 1,498,750,507 | 398,227,192 | 463,498,599 |
+| `pipeline12_q15` | 1,498,750,507 | 231,525,615 | 463,498,599 |
 | `pipeline_float` | 2,391,686,215 | 102,590,477 | 419,186,490 |
-| `pipeline_q15` | 1,020,281,310 | 137,792,386 | 204,476,476 |
+| `pipeline_q15` | 1,020,281,310 | 109,235,651 | 204,476,476 |
 | `pipeline_q31` | 1,102,554,828 | 173,088,119 | 205,223,931 |
 <!-- ICOUNT:END -->
 
diff --git a/async/bench/baselines.json b/async/bench/baselines.json
index 465c03b..70abb6c 100644
--- a/async/bench/baselines.json
+++ b/async/bench/baselines.json
@@ -21,9 +21,9 @@
     "kernel_float": 109298076,
     "kernel_q15": 192431957,
     "kernel_q31": 221164795,
-    "pipeline12_q15": 398227192,
+    "pipeline12_q15": 231525615,
     "pipeline_float": 102590477,
-    "pipeline_q15": 137792386,
+    "pipeline_q15": 109235651,
     "pipeline_q31": 173088119
   }
 }
diff --git a/bridge/README.md b/bridge/README.md
index fbb29c4..ec0e0bc 100644
--- a/bridge/README.md
+++ b/bridge/README.md
@@ -154,13 +154,13 @@ Executed instructions per fixed workload (`bridge/bench/icount/`), measured unde
 |---|---:|---:|---:|
 | `down_float_eco` | 1,720,707,553 | 73,794,800 | 304,636,182 |
 | `down_float_tr` | 5,473,297,976 | 214,977,684 | 944,365,072 |
-| `down_q15_eco` | 173,755,176 | 57,208,782 | 45,676,947 |
-| `down_q15_se` | 130,967,926 | 46,983,269 | 33,235,098 |
+| `down_q15_eco` | 173,755,176 | 22,404,812 | 45,676,947 |
+| `down_q15_se` | 130,967,926 | 17,749,381 | 33,235,098 |
 | `down_q31_eco` | 244,985,862 | 96,697,327 | 45,622,550 |
 | `up_float_eco` | 1,231,730,349 | 55,451,902 | 220,214,287 |
 | `up_float_tr` | 3,110,380,470 | 126,303,581 | 533,810,335 |
-| `up_q15_eco` | 133,914,472 | 44,556,679 | 35,990,378 |
-| `up_q15_se` | 103,390,933 | 39,050,794 | 27,424,077 |
+| `up_q15_eco` | 133,914,472 | 19,095,905 | 35,990,378 |
+| `up_q15_se` | 103,390,933 | 17,493,186 | 27,424,077 |
 | `up_q31_eco` | 184,954,171 | 72,647,042 | 36,007,820 |
 <!-- ICOUNT:END -->
 
diff --git a/bridge/bench/baselines.json b/bridge/bench/baselines.json
index 4d55d4c..2fea9ad 100644
--- a/bridge/bench/baselines.json
+++ b/bridge/bench/baselines.json
@@ -26,13 +26,13 @@
   "m55": {
     "down_float_eco": 73794800,
     "down_float_tr": 214977684,
-    "down_q15_eco": 57208782,
-    "down_q15_se": 46983269,
+    "down_q15_eco": 22404812,
+    "down_q15_se": 17749381,
     "down_q31_eco": 96697327,
     "up_float_eco": 55451902,
     "up_float_tr": 126303581,
-    "up_q15_eco": 44556679,
-    "up_q15_se": 39050794,
+    "up_q15_eco": 19095905,
+    "up_q15_se": 17493186,
     "up_q31_eco": 72647042
   }
 }
diff --git a/rational/PLAN.md b/rational/PLAN.md
index f15dc1d..0eb8057 100644
--- a/rational/PLAN.md
+++ b/rational/PLAN.md
@@ -906,19 +906,27 @@ plugin, `bench/baselines.json`; the README carries the full table):
 | Workload | Cortex-M33 | Cortex-M55 | Hexagon |
 |---|---:|---:|---:|
 | `down2_float_eco` | 366,459,700 | 24,577,869 | 72,734,422 |
-| `down2_q15_eco` | 47,494,712 | 25,070,113 | 18,554,089 |
+| `down2_q15_eco` | 47,494,712 | 19,806,582 | 18,554,089 |
 | `up2_float_eco` | 732,658,864 | 43,442,565 | 137,930,738 |
-| `up2_q15_eco` | 67,354,778 | 47,493,112 | 28,133,275 |
+| `up2_q15_eco` | 67,354,778 | 34,150,590 | 28,133,275 |
 | `up3_float_eco` | 1,407,620,075 | 75,330,937 | 254,903,952 |
-| `up3_q15_eco` | 92,695,694 | 74,874,023 | 39,793,932 |
-| `construct_q15_eco` | 774,741 | 33,682 | 183,854 |
-
-One finding, recorded for the codegen levers: on the M55, Q15 is not yet
-faster than float (↓2 25.07 M against 24.58 M, ↑2 47.49 M against
-43.44 M), where on the M33 it executes 7.7–15× fewer instructions and on Hexagon
-3.9–6.4× fewer (the ↓2, ↑2 and ↑3 pairs).
-The Q15 dot is the generic scalar kernel; an MVE dual-MAC Q15 kernel is a
-lever after M6, with the sparse rows and the symmetry-halved table, each
+| `up3_q15_eco` | 92,695,694 | 51,156,121 | 39,793,932 |
+| `construct_q15_eco` | 774,741 | 33,098 | 183,854 |
+
+One finding, recorded for the codegen levers, and the first lever it
+pulled: at M6, Q15 on the M55 was no faster than float (↓2 25.07 M against
+24.58 M, ↑2 47.49 M against 43.44 M), where on the M33 it executes 7.7–15×
+fewer instructions and on Hexagon 3.9–6.4× fewer (the ↓2, ↑2 and ↑3
+pairs). The cause was the substrate's Q15 dot: arm-none-eabi-gcc 13 left it
+one scalar SMLALBB per tap on Helium. DspTap's Helium Q15 kernel
+(tap/DspTap#53: eight lanes per VMLALDAVA, bit-exact) took the M55 Q15 rows
+above to the counts shown — ↓2 −21 %, ↑2 −28 %, ↑3 −32 %, the by-4 chain
+−48 % — with every output bit, every float and Q31 count and every M33 and
+Hexagon count unchanged (bridge's Q15 workloads fell 55–62 % and async's
+Q15 pipelines 21–42 % on the same pin). Q15 is now 19 % (↓2) to 32 % (↑3)
+under float on the M55; what remains per output is the stage's own
+bookkeeping around the dot. The sparse rows, the symmetry-halved table and
+the Q15 decimators' per-branch quantization are the levers still open, each
 measured against these baselines.
 
 **Order and gating.** M0 lands in DspTap and the family bumps its pin
diff --git a/rational/README.md b/rational/README.md
index cc3c139..d743ec1 100644
--- a/rational/README.md
+++ b/rational/README.md
@@ -172,16 +172,16 @@ Executed instructions per fixed workload (`rational/bench/icount/`), measured un
 
 | Workload | Cortex-M33 | Cortex-M55 | Hexagon |
 |---|---:|---:|---:|
-| `construct_q15_eco` | 774,741 | 33,682 | 183,854 |
-| `down2_down2_q15_eco` | 62,508,360 | 54,506,280 | 22,251,668 |
+| `construct_q15_eco` | 774,741 | 33,098 | 183,854 |
+| `down2_down2_q15_eco` | 62,508,360 | 28,178,778 | 22,251,668 |
 | `down2_float_eco` | 366,459,700 | 24,577,869 | 72,734,422 |
 | `down2_float_tr` | 955,278,690 | 47,997,517 | 174,664,319 |
-| `down2_q15_eco` | 47,494,712 | 25,070,113 | 18,554,089 |
+| `down2_q15_eco` | 47,494,712 | 19,806,582 | 18,554,089 |
 | `down3_float_eco` | 476,573,580 | 31,908,454 | 90,345,997 |
-| `down3_q15_eco` | 51,977,458 | 28,017,447 | 19,350,211 |
+| `down3_q15_eco` | 51,977,458 | 21,227,446 | 19,350,211 |
 | `up2_float_eco` | 732,658,864 | 43,442,565 | 137,930,738 |
 | `up2_float_tr` | 1,961,674,119 | 89,901,988 | 340,655,706 |
-| `up2_q15_eco` | 67,354,778 | 47,493,112 | 28,133,275 |
+| `up2_q15_eco` | 67,354,778 | 34,150,590 | 28,133,275 |
 | `up3_float_eco` | 1,407,620,075 | 75,330,937 | 254,903,952 |
-| `up3_q15_eco` | 92,695,694 | 74,874,023 | 39,793,932 |
+| `up3_q15_eco` | 92,695,694 | 51,156,121 | 39,793,932 |
 <!-- ICOUNT:END -->
diff --git a/rational/bench/baselines.json b/rational/bench/baselines.json
index be3fa4a..119093d 100644
--- a/rational/bench/baselines.json
+++ b/rational/bench/baselines.json
@@ -28,17 +28,17 @@
     "up3_q15_eco": 92695694
   },
   "m55": {
-    "construct_q15_eco": 33682,
-    "down2_down2_q15_eco": 54506280,
+    "construct_q15_eco": 33098,
+    "down2_down2_q15_eco": 28178778,
     "down2_float_eco": 24577869,
     "down2_float_tr": 47997517,
-    "down2_q15_eco": 25070113,
+    "down2_q15_eco": 19806582,
     "down3_float_eco": 31908454,
-    "down3_q15_eco": 28017447,
+    "down3_q15_eco": 21227446,
     "up2_float_eco": 43442565,
     "up2_float_tr": 89901988,
-    "up2_q15_eco": 47493112,
+    "up2_q15_eco": 34150590,
     "up3_float_eco": 75330937,
-    "up3_q15_eco": 74874023
+    "up3_q15_eco": 51156121
   }
 }
diff --git a/submodules/dsptap b/submodules/dsptap
index 537ab30..d646905 160000
--- a/submodules/dsptap
+++ b/submodules/dsptap
@@ -1 +1 @@
-Subproject commit 537ab30d31d3ab640e5ccccd1d9562b713b8a339
+Subproject commit d646905a47aa11ca9d1bcbcd36a28081cce8c4dc